A hard task, yes. But try!

1. Don't Play That Song
2. I Surrender
3. Without You
4. Stuff Like That There
5. Before Your Love
6. You're All I Need
7. Walk on By
8. A Moment Like THis
9. Think Twice
10. Natural Woman
11. It's Raining Men
12. RESPECT (Top 2)
13. RESPECT (Semifinals)

Hmm hard. I liked all her performances, so let's see...

A++s
1. I Surrender
2. Without You
3. You're All I Need
4. Stuff Like That There
A+s
5. A Moment Like This
6. Don't Play That Song
As
7. Natural Woman
8. RESPECT (Semifinals)
9. Before Your Love
A-s
10. It's Raining Men
11. Walk on By
12. RESPECT (Top 2)
13. Think Twice

1. Stuff Like That There (Best)
2. Without You
3. A Moment Like This
4. Natural Woman
5. Think Twice
6. RESPECT (Semifinals)
7. RESPECT (Top 2)
8. Walk on By
9. Don't Play That Song
10. You're All I Need
11. Before Your Love
12. It's Raining Men
13. I Surrender(Worst)

I'm thinking about fixing my list... because it changes almost every time I listen to them. But eh. I'll wait.

I've seen some of her performances, not all of them. Is there anywhere where I can download them?

I'm not going to rank them, I'm just going to say Stuff Like That There is the best.